Accommodative intraocular lens that ejects post capsular opacification and self-centers

ABSTRACT

Described is an accommodating intraocular lens with a bi-convex, bi-aspheric, smooth surfaced optic held inside an anterior annulus via tabs. A second larger diameter annulus is positioned posteriorly and connects via a sloped surface to where the annuluses are at a maximum separation when viewing NEAR objects and minimum separation in the FAR position. The sloped surface is cut into ribbons, tabs and/or other annuluses without pushing the surfaces into the capsule when implanted; therefore, only the anterior and posterior annuluses have a force component against the capsule. The proximal edge of the anterior annulus is anterior to the apex of the anterior surface of the optic. The anterior capsule resting on the annulus leaves space for hydration of the capsule and reduces potential warpage of the optic. The annulus edge is designed to scrape posterior capsular opacification from the capsule.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates generally to intraocular lenses and morespecifically to an accommodating intraocular lens having a hapticcomprising two or more annuluses connected together by one or moreribbons or tabs. The ribbons are disposed in parallel to the annuluseswhile the tabs are disposed radially to the annuluses. Together, theribbons and tabs provide a spring-like capability to the haptic suchthat the annuluses are at a maximum separation when viewing NEAR objectsand minimum separation when viewing FAR objects. The intraocular lens isuseful for replacing natural lenses diseased by cataracts and otherconditions.

Description of Related Art

Anatomy

FIG. 1 shows the clear portion of the eye, cornea (1), and functions asthe window to the remainder of the eye and refracts (bends) light. Justbehind the cornea is the anterior chamber (2) filled with a clearwatery, salty liquid (aqueous humor). At the back of the anteriorchamber is the colored iris (4); having an opening, pupil (3), whichchanges size regulating the amount of light passing into the eye. Thecornea and white portion of the eye, sclera (10), meet at a pointdefined as the limbus (7). The most distal point from the prime meridianof the iris attaches just in front of the limbus. Much of the ciliarybody (6) is attached to the sclera. The inside surface of the sclera isattached to the choroid (12). A study by Moses (see R. A. Moses,“Detachment of cilary body-anatomical and physical considerations”,Investigative Ophthalmology, 1965, 4(5): 935-941) implicated even indead eyes the choroid is under tension and in all sectors has elasticitysimilar to soft rubber with a significant tensile strength. It is wellknown that while the cornea will collapse during cataract surgery, thesclera maintains its dome shape. The lamellar (11) tissue holds thechoroid and sclera tissues together. The retina (13) attaches to thechoroid and is a delicate light-sensitive membrane lining the innereyeball and connected by the optic nerve to the brain. The space betweenthe natural lens and the retina (13) is filled with vitreous humor (14),a clear jelly-like substance. The posterior chamber (5) is the spacebetween the iris (4) and anterior capsule (17) of the natural(crystalline) lens (16). The anterior zonule fibers (8) and theposterior zonule fibers (9) are fine hair-like structures that attach tothe ciliary body (6) with the opposite ends attached to the naturallens. From ultrasound data it is estimated the length of the zonulesoutside the ciliary body to be about 1.4 millimeters (mm) for theanterior and 2.3 mm for the posterior. Nutrimental aqueous is processedby the ciliary body for use by the optical surfaces without bloodvessels, which include the cornea and natural lens. The anterior zonulefibers (8) attach (18) very near the end of the anterior capsule (17).The opposite ends extend into the ciliary body (6) where the anteriorzonules terminate very close to the point where the iris (4) attaches tothe cornea (1).

As shown in FIG. 2, the posterior zonules attach (20) more tangentiallyto the posterior capsule (19) with the opposite end extending into theciliary body and arching toward the choroid (12). Pictures (see J WRohen, “Scanning electron microscopic studies of the zonular apparatusin human and monkey eyes”, Investigative Ophthalmology & Visual ScienceFebruary 1979, Vol. 18, 133-144 (“Rohen, 1979”)) and cadaver reviewshave shown the zonules are not just loose fibers, but are woven into mator carpet appearance, which adds considerable strength. The fibers arefirmly attached to the ciliary processes. The outer shell of the natural(crystalline) lens capsule (16) is a smooth, thin, transparent, delicatelayer of connective tissue. In younger people when the ciliary body (6)increases in size, removing tension, the natural lens assumes a moreglobular shape as desired for NEAR vision (see Rohen, 1979).

As can be seen by the FIG. 3, when looking at FAR objects the ciliarybody reduces in size adding tension to the zonules and stretching thenatural lens capsule to a flatter shape (22). Inside the anteriorportion of the natural lens capsule the epithelium pumps nutrients andfluids from the aqueous into the cavity. Throughout life the lensepithelium generates lens fibers that make up the bulk of the lens mass.They are long, thin, transparent cells which are typically 4 to 7microns in diameter and up to 12 mm long. In young eyes the fibers canbe positioned from the anterior to the posterior pole. The bunching ofthe fibers gives the appearance of a laminar assembly with the index ofrefraction varying from 1.4064 at the prime meridian to 1.3864 near thedistal ends of the natural lens. The polar circumference of the naturallens is the arc distance of the anterior capsule plus the arc distanceof the posterior capsule plus twice the arc distance of the equatorialregion. It is well known in the industry when implanting intraocularlenses that are shaped like a coin (relatively flat disc lens) thediameter of the lenses should be approximately 10.5 mm; therefore, thearc circumference of the natural lens capsule must be twice the 10.5 mmplus an allowance for the edge thickness. Many believe the fibersgenerated by the natural lens anterior capsule epithelium move towardthe posterior capsule depositing between the soft material (cortex) ofthe posterior capsule and the last layer of fibers with the processcontinuing until the natural lens capsule becomes too large to changeshape. More logically as the person ages the fibers do not have enoughenergy to force their way between the posterior capsule and previousfibers and must remain in the equatorial area. The extra fibers preventthe capsule from assuming the full NEAR position (21); therefore, theamount of accommodation is reduced. Over time the density of the fibersincrease until a cataract is formed. Coleman (see D. Jackson Coleman,“On the Hydraulic Suspension Theory of Accommodation”, Transactions ofthe American Ophthalmological Society Vol. LXXXIV 1986, “Coleman, 1986”)and Bernal, Parel, and Manns (see Andres Bernal, Jean-Marie Parel, andFabrice Manns, “Evidence for Posterior Zonular Fiber Attachment on theAnterior Hyaloid Membrane”, IOVS November 2006 Volume 47 No. 11)discussed a ring (hyaloid membrane) that is sheets of condensationwithin the vitreous. The membrane attaches to the ora serrata, which isthe edge of the retina located about 6.5 mm behind the corneo-scleraljunction (limbus). The membrane attaches to the back of the natural lensincluding the woven zonular fibers and adds strength creating a pressuredifferential diaphragm between the vitreous and aqueous cavities. It iswell known in the industry and concluded by Coleman that duringaccommodation the natural lens gets thicker along the plane of the primemeridian and thinner distally from the prime meridian. Coleman's workconcluded the pressure in the vitreous is slightly higher than thepressure in the aqueous during NEAR vision and the reverse for FARvision; however, the differential pressure of the vitreous betweenreadings was slight. The volume of the vitreous cavity is significantlylarger than the aqueous cavity; therefore, a given amount of aqueousvolume change would give a significantly larger change in pressure inthe aqueous than the vitreous. There will be a positive force pushinganteriorly on the natural lens or an implanted intraocular lens when theeye is looking at NEAR objects and a positive force pushing posteriorlywhen the eye is looking at FAR objects.

Accommodation

It is readily accepted as shown in FIG. 4 that distant objects (FAR)assume the rays to be parallel light (23) with the object at infinity.For reading or looking at closer work it is assumed the light is takenfrom a point light (24), the point is not to scale. The cornealrefraction is approximately the same. Since the light rays need toarrive at or near the fovea (15), the natural lens changes shape makingthe structure more globular. As explained by Coleman (see Coleman, 1986)the ciliary processes relax the natural lens in the NEAR position andadd tension in the FAR position stretching the natural lens into a moreflattened shape. In both the NEAR and FAR positions corneal refraction(25) accounts for approximately ⅔rds of the desired refraction. Thelight travels from the cornea through the pupil to the natural lensanterior surface where the rays are refracted (26) then travel to theposterior surface, which again refracts (27) the light coming to a pointon or near the fovea (15).

Intraocular lenses for FAR vision and multi-focal lenses for NEAR visionare readily available. One older model is shown in FIG. 5 with thinangulated haptics which are spring like extensions of the optic. Fromtip to tip the lenses are normally 11.2 mm to 12.5 mm with some evenlarger, which distorts the capsule and stretches it to an almost flatsurface leaving little movement for accommodation. Multi-focal lenses bydefinition have multiple images creating glare. Professionals in thefield are striving for perfection, yet to achieve the desired outcomeposterior capsular opacification (PCO) must be reduced to a level thatdoes not impede the vision of the patient. A perfect lens would allow asafe effective intraocular lens implantation when a person first neededreading spectacles and would provide almost perfect vision for theremainder of their life.

Posterior Capsular Opacification, PCO

After cataract surgery the inside surfaces (epithelium) of the naturallens anterior surfaces continue to generate cells, which migrate towardthe posterior surface of the capsule. Earlier lens models had roundededges allowing the fibers to easily penetrate between the posteriorsurface of the lenses and the capsule impeding vision and contrastsensitivity. This is Posterior Capsular Opacification, PCO. Models withsharp edges delay the visual effects of PCO; however, with time thefibers grow in front of the optic reducing vision. Historically hapticsspring like structures position the optic within the capsule. The springeffect stretches the capsule forcing it to become almost flat. Somehaptic designs retard the growth of PCO in quadrants where the hapticsare present; yet, capsule remnants and an edge of a haptic often form atunnel that can accelerate the movement of the cells directly to theedge of the optic. To obtain long term satisfactory results PCO must beblocked in all directions. When intraocular lenses stretch the capsuleremnants tightly little aqueous can reach the inside surfaces leaving anunhealthy capsule. Three dimensional intraocular lenses are beingdeveloped and may stretch the equatorial region until the area resemblesa continuation of the posterior and anterior surfaces. Such lenses canreduce the tendency for PCO collection in the equatorial region;however, PCO still collects in other places, especially near the contactarea between the lens and the posterior capsule. If designed for goodaqueous flow inside the natural lens cavity three dimensional lenses cancontribute to healthier lens capsules. It has recently been reportedthat if the PCO particles are separated from the tissue and saturatedwith aqueous they will not reattach and can be carried out of the eyethrough the natural aqueous process. The treatment of PCO also involvesa risk to the eye, and therefore, it is important that strategies toretard and prevent PCO may contribute to preserving visual acuity inpatients over their lifetimes. According to an article by Abhay RVasavada and others, “capsular opacification, in particular PCO, stillremains a physiological complication of uneventful cataract surgery”(see Abhay R Vasavada; Shetal M Raj; Gauri D Shah; Mayank A Nanavaty.Posterior Capsule Opacification After Lens Implantation”, Expert RevOphthalmol. 2013; 8(2):141-149) Methods currently available cannotsignificantly decrease the rate of PCO. The quest for its eradication isongoing. Related efforts in this area include those described in U.S.Pat. Nos. 9,084,674; 8,523,942; 8,034,107; 7,871,437; 8,377,125;7,806,929; 7,763,069; 7,662,180; 6,932,839; and 5,496,366. Yet, thereremains a need in the art for an intraocular lens that addresses thisissue.

SUMMARY OF THE INVENTION

Embodiments of the invention provide an accommodating intraocular lenswith a bi-convex, bi-aspheric, smooth surfaced optic held inside ananterior annulus via tabs. A second larger diameter posterior annulus ispositioned posteriorly and connects via a sloped surface to where theannuluses are at a maximum separation when viewing NEAR objects andminimum separation in the FAR position. The sloped surface is cut intoribbons, tabs and/or additional annuluses without pushing the surfacesinto the capsule when implanted; therefore, only the anterior andposterior annuluses have a force component against the capsule. Theproximal edge of the anterior annulus is anterior to the apex of theanterior surface of the optic. The anterior capsule resting on theanterior annulus leaves space for hydration of the capsule. It alsoreduces potential warpage of the optic. The anterior annulus edge isdesigned to scrape PCO from the capsule. When changing accommodativestates, aqueous turbulence will increase the removal of PCO. Theposterior annulus and capsule squeeze PCO when moving from the FAR toNEAR positions. Once saturated with aqueous fluid the PCO can be carriedout of the eye via natural physiological processes.

In embodiments, the annuluses are held together via tabs attached toribbons which are cut into the haptic slope forming the equivalent ofcomplex cantilevered beams. The ribbons can be parallel to (orconcentric with—depending on whether the device is in a relaxed orcompressed state) the anterior and posterior annuluses or angled. Thetabs can also be attached to additional annuluses. When the intraocularlens is implanted, the anterior and posterior annuluses in contact withthe segments of the capsule stretch each segment tight. With tightcapsular segments and differential pressures the vitreous pressure ishigher than the aqueous for NEAR vision and the reverse for distantvision. The differential pressures allow the optic to be held inposition. If the surgeon refracts the patient slightly hyperopic theoptic is expected to stop at emmetropia. For lenses manufactured withstiffer materials, the lens can be squeezed until collapsed and expectedto remain in such a state long enough for implantation using onlyforceps. Forces placed on the anterior and posterior annuluses viacapsule remnants will force centration of the lens without surgicalassistance.

Specific aspects of the invention include Aspect 1, which provides anintraocular lens with an optic placed inside an anterior annulus andhaving a posterior annulus that is larger in diameter than the anteriorannulus, wherein the annuluses are connected by way of a haptic slopesurface that is sloped to where the annuluses are at a maximumseparation along a plane perpendicular to the radii of the annuluseswhen viewing NEAR objects and collapsed to where the anterior annulusrests inside or near the posterior annulus when viewing FAR objects.

According to Aspect 2, the lens as in Aspect 1 is provided where thecomponents connecting the anterior and posterior annuluses are indifferent planes parallel to the prime meridian and do not have a forcecomponent in a plane that will place force on the capsule duringmovement.

Aspect 3 is the lens in either of Aspects 1 and 2 where the optic isbi-convex.

Aspect 4 is the lens in any one of Aspects 1-3 where the optic isbi-aspheric with smooth surfaces that can vary in power to reduce theprofile of the lens to allow more travel space for accommodation.

Aspect 5 is the lens in any one of Aspects 1-4 where the anteriorannulus and the optic are held together via a series of attachment tabs.

Aspect 6 is the lens in any one of Aspects 1-5 where the anteriorannulus has a point that is anterior to the apex of the optic.

Aspect 7 is the lens in any one of Aspects 1-6 where the anteriorcapsule rest against the apex of the anterior annulus preventing warpageof the optic.

Aspect 8 is the lens in any one of Aspects 1-7 where the space betweenthe tabs allows hydration of the natural lens capsule.

Aspect 9 is the lens in any one of Aspects 1-8 where the anteriorannulus proximal edge scrapes some PCO free allowing saturation withaqueous and removal from the eye via normal physiological processes.

Aspect 10 is the lens in any one of Aspects 1-9 where changingaccommodative state creates aqueous turbulence placing PCO into theaqueous for saturation.

Aspect 11 is the lens in any one of Aspects 1-10 where the posteriorannulus rest over the posterior zonular-capsular junction.

Aspect 12 is the lens in any one of Aspects 1-11 where PCO is trappedbetween the posterior annulus and the posterior capsule.

Aspect 13 is the lens in any one of Aspects 1-12 where the annuluses areheld together by ribbons.

Aspect 14 is the lens in any one of Aspects 1-13 where the ribbons arelocated along the haptic slope.

Aspect 15 is the lens in any one of Aspects 1-14 where the ribbons are aseries of cantilevered beams.

Aspect 16 is the lens in any one of Aspects 1-15 where the cantileveredbeams function as a complex spring.

Aspect 17 is the lens in any one of Aspects 1-16 where the anterior andposterior annuluses are held together by additional annuluses.

Aspect 18 is the lens in any one of Aspects 1-17 where the annuluses areconnected by tabs.

Aspect 19 is the lens in any one of Aspects 1-18 where the anteriorcapsule is stretched tightly over the anterior annulus.

Aspect 20 is the lens in any one of Aspects 1-19 where the posteriorcapsule is stretched tightly over the posterior annulus.

Aspect 21 is the lens in any one of Aspects 1-20 where when in the NEARposition, the vitreous force is greater than the aqueous force aidingthe movement or holding the lens in the NEAR position.

Aspect 22 is the lens in any one of Aspects 1-21 where when stress isadded to the zonules by the ciliary body the optic and anterior annuluscollapse forcing the optic posteriorly.

Aspect 23 is the lens in any one of Aspects 1-22 where when in the FARposition the aqueous force is greater than the vitreous force holdingthe lens in the FAR position.

Aspect 24 is the lens in any one of Aspects 1-23 where any remaining PCOis collected along the posterior capsule and the outside of theposterior annulus, which can form a PCO annulus.

Aspect 25 is the lens in any one of Aspects 1-24 where when movingtoward NEAR vision the posterior capsule squeezes the PCO against theposterior annulus ejecting PCO into the aqueous.

Aspect 26 is the lens in any one of Aspects 1-25 where the surgeonrefracts the patient slightly hyperopic allowing the force on thecapsule to stop movement at emmetropia for FAR vision.

Aspect 27 is the lens in any one of Aspects 1-26 where when manufacturedwith a relatively stiff material the lens can be squeezed and implantedusing only forceps and allowed to open slowly after implantation.

Aspect 28 is the lens in any one of Aspects 1-27 where anatomicalcapsular forces on the anterior and posterior annuluses will move thelens until centration is achieved.

Aspect 29 is an intraocular lens comprising: an optic; and a hapticsupporting the optic and comprising an outer annulus and an innerannulus, wherein the outer annulus has a larger radius than a radius ofthe inner annulus.

Aspect 30 is the intraocular lens of Aspect 29, wherein the innerannulus is in communication with the optic by way of a plurality oftabs.

Aspect 31 is the intraocular lens of Aspect 29 or 30, wherein the innerannulus is in communication with the outer annulus by way of a pluralityof tabs and/or a plurality of ribbons and/or a plurality of intermediateannuluses.

Aspect 32 is the intraocular lens of any of Aspects 29-31, wherein theinner annulus is in communication with the outer annulus by way of aplurality of tabs and a plurality of ribbons, wherein each of theribbons comprises an arcuate bend.

Aspect 33 is the intraocular lens of any of Aspect 32, wherein thearcuate bend is a 180 degree bend.

Aspect 34 is the intraocular lens of any of Aspects 29-33, wherein thehaptic is flexible and capable of disposing the optic in any positionbetween the inner annulus and the outer annulus.

Aspect 35 is the intraocular lens of any of Aspects 29-34, wherein theinner annulus is in communication with the outer annulus by way of atleast one intermediate annulus, and tabs connecting the inner annulus tothe at least one intermediate annulus, and tabs connecting the at leastone intermediate annulus to the outer annulus.

Aspect 36 is the intraocular lens of any of Aspects 29-35, wherein theat least one intermediate annulus comprises two intermediate annuluses.

Aspect 37 is the intraocular lens of any of Aspects 29-36, wherein thehaptic slopes outwardly from the inner annulus to the outer annulus.

Aspect 38 is an intraocular lens comprising: an optic; a haptic incommunication with the optic, comprising: a first annulus; a secondannulus; a plurality of tabs connecting the optic and the annuluses;wherein a cross-section of the intraocular lens along a planeperpendicular to a diameter of the intraocular lens reveals that thehaptic is sloped.

Aspect 39 is the intraocular lens of Aspect 38, wherein the haptic isflexible and capable of disposing the optic in any position between thefirst annulus and the second annulus.

Aspect 40 is the intraocular lens of any of Aspects 38-39, wherein thefirst annulus is in communication with the second annulus by way of atleast one intermediate annulus, and tabs connecting the first annulus tothe at least one intermediate annulus, and tabs connecting the at leastone intermediate annulus to the second annulus.

Aspect 41 is an intraocular lens comprising: an optic; a flexible hapticcomprising a network of annuluses and tabs configured to provideflexibility to the haptic from a compressed state to a relaxed state;wherein when the haptic moves from a relaxed state to a compressedstate, the annuluses are capable of moving toward one another; andwherein when the haptic moves from a compressed state to a relaxedstate, the annuluses are capable of moving away from one another.

Aspect 42 is the intraocular lens of Aspect 41, wherein during use by asubject the annuluses and tabs function as a spring such that theannuluses are at a maximum separation when the subject is viewing nearobjects and at a minimum separation when the subject is viewing farobjects.

Aspect 43 is the intraocular lens any of Aspects 29-42, wherein theoptic is bi-convex or wherein the optic is bi-aspheric.

Additional aspects include Aspect 44, which provides an intraocular lenscomprising an optic, a haptic comprising at least a first and secondannulus concentrically disposed and surrounding the optic, wherein thefirst annulus has a radius that is greater than a radius of the secondannulus.

Aspect 45 is the intraocular lens of Aspect 44, wherein at least one ofthe annuluses is in communication with the optic by way of a pluralityof tabs disposed radially to the annuluses.

Aspect 46 is the intraocular lens of either of Aspect 44 or 45, whereinat least the first and second annulus are in communication with eachother by way of a plurality of tabs disposed radially to the annulusesand/or ribbons disposed concentrically to the annuluses.

Aspect 47 is the intraocular lens of any one of Aspects 44-46, whereineach of the ribbons comprises a first portion concentrically disposed toa second portion, wherein the first portion and second portion are incommunication with each other by way of an arcuate bend and form acantilevered structure.

Aspect 48 is the intraocular lens of any one of Aspects 44-47, whereinthe first ribbon portion and second ribbon portion are concentricallydisposed between the first and second annulus.

Aspect 49 is the intraocular lens of any one of Aspects 44-48, whereinthe first annulus and second annulus are in communication with theribbons by way of one or more tabs disposed radially to the ribbons andannuluses.

Aspect 50 is the intraocular lens of any one of Aspects 44-49,comprising at least a third annulus, wherein the first, second, andthird annulus are concentrically disposed and surrounding the optic andin communication with each other by way of a plurality of tabs disposedradially to the annuluses.

Aspect 51 is the intraocular lens of any one of Aspects 44-50,comprising at least a fourth annulus, wherein the first, second third,and fourth annuluses are concentrically disposed and surrounding theoptic and in communication with each other by way of a plurality of tabsdisposed radially to the annuluses.

Aspect 52 is the intraocular lens of any one of Aspects 44-51, wherein across-section of the intraocular lens through a lens diameter revealsthat the haptic is sloped at an acute angle relative to the optic.

Aspect 53 is the intraocular lens of any one of Aspects 44-52, whereinthe optic is bi-convex.

Aspect 54 is the intraocular lens of any one of Aspects 44-53, whereinthe optic is bi-aspheric.

Aspect 55 is the intraocular lens of any one of Aspects 44-54, whereinthe optic has a circumference that is disposed in a first plane and atleast one of the annuluses has a circumference that is disposed in adifferent plane that is in parallel relative to the first plane.

Aspect 56 is the intraocular lens of any one of Aspects 44-55, whereinthe first annulus has a circumference disposed in a first plane and thesecond annulus has a circumference that is disposed in a second planethat is in parallel relative to the first plane.

Aspect 57 is the intraocular lens of any one of Aspects 44-56 whereinthe ribbons form a cantilevered structure.

Aspect 58 is the intraocular lens of any one of Aspects 44-57, whereinthe arcuate bend is a 180 degree bend.

Aspect 59 is an intraocular lens comprising an optic, a haptic incommunication with and surrounding the optic, comprising a first annulushaving a first radius, a second annulus having a second radius, a seriesof tabs and/or cantilevered structures disposed between and incommunication with the first annulus and the second annulus, wherein thefirst radius is greater than the second radius, wherein a cross-sectionof the intraocular lens through a lens diameter reveals that the hapticis sloped at an acute angle.

Aspect 60 is an intraocular lens comprising an optic, a hapticcomprising at least a first and second annulus, and a series of tabsand/or bands in communication with the annuluses, wherein the firstannulus has a radius that is greater than a radius of the secondannulus; wherein the tabs are disposed radially to the annuluses and/orbands are disposed concentrically to the annuluses.

Aspect 61 is the intraocular lens of Aspect 60, wherein two adjacentbands are in communication with each other by way of an arcuate bend atone end, forming a cantilevered structure.

Aspect 62 is an intraocular lens comprising an optic, a hapticcomprising a network of annuluses, tabs, and bands, wherein theannuluses and bands are disposed concentrically surrounding the opticand the tabs are disposed radially to the annuluses and bands, whereineach annulus has a circumference, and wherein each annulus circumferenceis disposed in a different plane and is greater than a circumference ofan adjacent annulus.

Aspect 63 is the intraocular lens of Aspect 62, wherein two adjacentbands are in communication with each other by way of an arcuate bend atone end, forming a cantilevered structure.

Aspect 64 is the intraocular lens of Aspect 44, wherein during use theribbons and tabs function as a complex spring such that the first andsecond annuluses are at a maximum separation when viewing near objectsand minimum separation when viewing far objects.

Aspect 65 is the intraocular lens of Aspect 60, wherein during use thebands and tabs function as a complex spring such that the first andsecond annuluses are at a maximum separation when viewing near objectsand minimum separation when viewing far objects.

Aspect 66 is the intraocular lens of Aspect 62, wherein during use thebands and tabs function as a complex spring such that the first andsecond annuluses are at a maximum separation when viewing near objectsand minimum separation when viewing far objects.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate certain aspects of embodiments ofthe present invention, and should not be used to limit the invention.Together with the written description the drawings serve to explaincertain principles of the invention.

FIG. 1 is a diagram showing a cross-section of a human eye in the NEARposition where the natural lens is more globular. The zonules are shownpassing through the ciliary body.

FIG. 2 is a diagram depicting the eye in the FAR position, with thenatural lens flatter in shape.

FIG. 3 is a diagram which compares the natural lens overlaid in the NEARand FAR positions.

FIG. 4 is a diagram depicting a top cross-sectional view which showsparallel rays as would be the case when looking at distant objectsapproaching the eye from infinity; while the lower view shows lightcoming from a point source similar to reading.

FIG. 5 is a diagram showing an older model lens which collapses thecapsule tightly against the lens surfaces.

FIG. 6 is a diagram showing a 3-dimensional perspective view of apreferred embodiment of the invention.

FIG. 7 is a diagram showing a top planar view of a preferred embodimentof the invention.

FIG. 8A is a diagram showing a cross-sectional view of a preferredembodiment of the invention prior to cutting the haptic ribbons.

FIG. 8B is a diagram showing a view through the centerline of FIG. 7showing the opening between the optic edge (29) and the anterior annulusproximal edge (31).

FIG. 9A is a diagram showing a cross-sectional view of an eye showing apreferred embodiment of the invention.

FIG. 9B is a diagram showing a cross-sectional view of an eye showing apreferred embodiment of the invention with the lens offset to the leftside.

FIG. 10 is a diagram showing a cross section of a portion of the view ofFIG. 9.

FIG. 11 is a diagram showing a preferred embodiment of the inventionimplanted and squeezed into the FAR position.

FIG. 12 is a diagram showing a cross section of a portion of the view ofFIG. 11.

FIG. 13 is a diagram showing an embodiment of the invention withmultiple annuluses.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS OF THE INVENTION

Reference will now be made in detail to various exemplary embodiments ofthe invention. It is to be understood that the following discussion ofexemplary embodiments is not intended as a limitation on the invention.Rather, the following discussion is provided to give the reader a moredetailed understanding of certain aspects and features of the invention.

Unless otherwise noted, definitions for ocular terminology included inthis specification can be found in the Dictionary of Eye Terminology byBarbara Cassin and Melvin L. Rubin (ISBN 0-937404-44-6); MerriamWebster's Medical Dictionary (ISBN 0-87779-914-8); or American HeritageCollege Dictionary Fourth Addition (ISBN-13; 978-0-618-8359-9 ISBN-10;0-618-83595-4). Other references that may provide background to theinvention include Fundamentals of Optics—by Francis Jenkins & Harvey E.White (ISBN 0-07-032330-3) and Optical Engineering Fundamentals by BruceH. Walker (ISBN-13: 978-0819475404; ISBN-10: 0819475408). Each of thesereferences is hereby incorporated by reference in their entireties.

The following definitions may be useful for aiding in understanding ofthe invention.

Accommodation—Increase in optical power by the eye in order to maintaina clear image as objects are moved closer.

Accommodative Intraocular Lens—A lens that functions with the muscles(ciliary) of the eye to allow or force the intraocular lens to moveanteriorly causing near objects to come into sharp focus.

Anterior Capsule—Front of the capsule enclosing the crystallinelens—Lies just behind the iris.

Anterior Capsular Opacification—Fogging of the anterior portion of thecapsule remnant after cataract extraction and intraocular lensimplantation. The fogging cells are attached to the capsule and notbetween the lens and capsule.

Anterior Capsulotomy—Surgically opening the front of the crystallinelens capsule in order to remove the crystalline lens.

Aphakia—Absence of the eye's crystalline lens.

Aqueous—Clear, watery fluid that fills the space between the backsurface of the cornea and the front surface of the vitreous, bathing thenatural lens. Produced by the ciliary processes. Nourishes the cornea,iris, and natural lens. Maintains intraocular pressure.

Aspheric Lens—A lens where the optical surfaces are not a portion of asphere.

Capsular Bag—Bag-like lens capsule remnant remaining after cataractremoval—Structure much like a thin lung or kidney. Used for placement ofan intraocular lens.

Capsular Fixation—When an intraocular lens is held in position byinsertion into the remnant of the natural lens capsule.

Capsule—See Capsular Bag—Elastic bag enveloping the eye's crystallinelens.

Capsulectomy—Surgical removal of part of the lens capsule.

Capsulorhexis—Opening in the lens capsule made in a continuous circularpattern for the removal of a cataractous natural lens and replacementwith an intraocular lens.

Capsulotomy—Incision to open the natural lens capsule.

Cataract—Opacification or cloudiness of the crystalline lens of the eyeto where enough light is retarded to decrease visual acuity.

Cataract Extraction—Removal of the cataractous natural lens of the eye.

Extracapsular—Method that leaves the rear portion of the lens capsuleintact.

Intracapsular—Method that removes the entire lens capsule.

Ciliary Body—Circumferential tissue inside the eye composed of theciliary muscle and ciliary processes. Controls the intraocular pressureand accommodation. Produces aqueous.

Ciliary Muscle—Portion of the ciliary body that connects to the zonulesthat attach to the natural lens capsule. Movement of the ciliary musclecauses movement of the zonules and in turn changes the shape of thenatural lens allowing accommodation.

Ciliary Sulcus—Groove in the posterior chamber between the ciliary bodyand the iris.

Convex Lens—Lens that is thicker in the center than the edges.

Haptic—Non-optical portion of an intraocular lens that supports the lensagainst the affixation tissue of the eye (the inside surfaces of thecapsule).

Hyperopia—Condition of the eye where the natural lens does notautomatically compensate by increasing the power needed by the patientfor clear vision. The image focuses behind the retina.

Hyperopic—Farsighted—Objects focus behind the retina.

Intraocular lens (IOL)—An artificial lens placed inside the eye. Oftenused after cataract surgery. Also used to correct for myopia orhyperopia.

HEMA (hydroxy-ethyl-methacrylate)—Plastic polymer used to make softcontact lenses. A chemical derivate of polymethylmethacrylate.

Multi-focal—Optical surface where light rays entering the surface atdifferent radial locations come to focus at different points.

Near Sightedness—Myopia—Light rays from distant objects come to focus infront of the retina.

Polymethylmethacrylate (PMMA)—Hard lens material with littleflexibility. Was the initial material used to make intraocular lenses.While newer hydrophilic and hydrophobic materials are being used, PMMAis still used to manufacture intraocular lenses.

Silicone—Soft contact lens and intraocular lens material that is softwithout maintaining hydration. Can be injection molded.

Milling Machine—Used in lens production to shape the haptics intospring-like structures to hold the optic in position.

Post Capsular Opacification, PCO—Fogging of the posterior portion of thecapsule remnant after cataract extraction and intraocular lensimplantation. The fogging cells are attached to the capsule and notbetween the lens and capsule.

Posterior Capsulotomy—An incision into the capsule behind an intraocularlens. Opens the capsule allowing light to pass through when the capsulehas opacified.

Posterior Chamber Intraocular Lens (PCIOL)—An artificial lens implantedinto the space behind the iris. Most often the lens is placed inside thecapsule remnant after cataract extraction.

Presbyopia—Refractive condition in which there is a diminished power ofaccommodation. Arises from a loss of elasticity of the crystalline lens.Occurs with aging.

Pseudophakia—State of having an intraocular lens implanted. Taking theplace of the eye's natural lens.

Trabecular Meshwork—Mesh-like structure inside the eye at theiris-scleral junction of the anterior chamber angle. Filters aqueousfluid and controls its flow out of the eye.

Vitreous—Transparent colorless gelatinous mass that fills the reartwo-thirds of the eye ball, between the natural lens and the retina.

Zonules—Radially arranged fibers that suspend the lens from the ciliarybody and hold it in position. During accommodation movement of theciliary body causes the forces on the zonules to change, which in turnchanges the shape of the natural crystalline lens.

Turning now to the figures, FIG. 6 shows an embodiment of a3-dimensional intraocular lens (IOL) in the NEAR position with over onemillimeter of movement. Additional accommodation from differentialpressures between the aqueous and vitreous is also possible. The lenscan be manufactured using high precision lathes available from multiplecompanies located within the United States. Manufacturing using 3Dprinting may also be considered for all or a portion of the device, suchas the support structure for the lens, including the annuluses, ribbons,and/or tabs. In any embodiment, the lens may be manufactured frommaterials such as polymethylmethacrylate (PMMA), silicone, hydrophobicacrylate, hydrophilic acrylate and collamer, and the like.

Referring to FIGS. 7, 8A, and 8B, a top planar view of an embodiment ofthe 3-dimensional lens is shown in FIG. 7 with the optic (28) showninside or surrounded by the anterior annulus (32). The optic edge (29)and the anterior annulus proximal edge (31) are connected via spacedattachment tabs (30). The attachment tabs can be equally spaced aroundthe annulus and/or lens or can be spaced at any interval. FIGS. 8A and8B provide cross-sectional views showing that the tabs (30) are the samethickness as the end of the member to which they are to be connected;therefore, the thickness varies across the cross-sections. For example,as shown, tab (30) has a greater thickness at the end connected withanterior annulus proximal edge (31) and a thinner thickness at the endconnected with optic edge (29). In FIG. 8B, tab (30) is shown separatedfrom the device to illustrate it in isolation. Distally attached to theanterior annulus is the haptic slope (39), which is initially cut into aconical section. FIG. 7 shows anterior attachment tabs (33) are cut intothe haptic slope connecting the anterior annulus to the anterior ribbon(34). The tabs are located at the center of the anterior ribbons and forthe preferred embodiment the ribbons are cut concentric to the anteriorannulus. When a distance to obtain the desired flexibility is achievedthe anterior ribbons (35) turn 180 degrees becoming posterior ribbons(36) and through tabs (37) attach to the posterior annulus (38). Thehaptic slope is cut to allow each member between the optic and posteriorannulus to come to the FAR position with separation between eachcomponent as to allow maximum movement of the lens optic without anylateral movement to place stress on the capsule remnants. In the NEARposition there is a small force from the natural lens capsule holdingthe lens in position. In the FAR position the lens is squeezedposteriorly. Individually the anterior and posterior ribbons (34, 36)would function much like a cantilevered beam (diving board); however,when connected (35) the function changes to be more like two layers of aleaf or complex spring. Within the eye the lens is designed to be atrest in the NEAR position. FIG. 8B shows an embodiment of abi-convex-bi-aspheric optic (28) which allows for a smooth surface and avery thin profile at the center of the lens, making the overallcross-section smaller, which reduces the incision size needed forimplantation. The aspherical design can allow adjustments of the opticto remove aberrations from the eye. The anterior annulus (32) isslightly higher than the apex of the anterior optic, which reduces thepossibility of warpage via contact with the anterior capsule. Thedifferential height plus the space between the optic edge and theanterior annulus allows clearance to provide aqueous flow for hydrationinside the capsule. With 3-dimensional lenses designed for accommodationthe natural lens capsular remnants are critical to prolongedanterior-posterior movement. The aqueous carries the needed nutrients tothe structures that do not contain blood vessels. The anterior annulusproximal surface (31) to the optic has a surface exposed to the anteriorcapsule that will remove some PCO generated via the capsule epithelium.The PCO removed from the epithelium is saturated with aqueous forremoval from the eye as the aqueous is removed via the trabeculum.

Turning to FIGS. 9A and 10, the anterior capsule 17 of the natural lensstretches against the anterior annulus (32) with a portion of thecapsule wrapping around the annulus. The posterior capsule (19)stretches against the posterior annulus (38) at or near thecapsular-zonular junction (20). Both surfaces stretch taut andtangentially to the respective annuluses pulling the surfaces flat andholding the lens in position. The space between the attachment points(41) is also tight in the near position and squeezed to occupy minimalspace in the far position. While most lenses are designed for a polarcapsular circumference of 21 millimeters; some eyes are smaller. If theeye has a smaller polar circumference, embodiments of the presentinvention automatically adjust to the size of the capsule for NEARvision. Some potential accommodation will be lost; however, significantaccommodation should still be available as only a small portion of thepotential movement should be needed for sizing. The lens in thepreferred embodiment is designed to place the posterior annulus (38) atthe 20-Posterior Zonule Capsule Connection, which gives additionalstrength as both surfaces weave together increasing the strength. Thelens is held in the capsule by the annuluses with some tension along theribbons. Only a small amount of tension is necessary to hold the lens inthe NEAR position.

As shown in FIGS. 9A and 10, when viewing NEAR objects the ciliaryprocesses remove tension on the zonules and the pressure in the vitreousis slightly higher than the pressure in the aqueous; therefore, the lensoptic rests in the most anterior position.

FIG. 9B shows a cross-sectional view with the lens offset to the leftside which puts the zonules in that section under compression and thezonules 180 degrees away in tension or at least less compression. Inaddition, the capsule between the zonule attachment points (41) isstretched tighter on the compression side resembling an arcuate. Thecombination of the forces will center the lens.

As shown in FIGS. 11 and 12, when viewing FAR objects the ciliaryprocesses place tension on the anterior and posterior zonules stretchingthe natural lens capsule which applies an anterior/posterior forcevector across the two annuluses which is transferred through the tabs tothe ribbons collapsing the IOL optic into the FAR position. The expecteddistance from the NEAR to the FAR position due to the ribbonsfunctioning as a complex spring is over one millimeter. The differentialvitreous/aqueous pressure is expected to provide additional movement.Since the annuluses are stretched tight there is no relative motionbetween the capsule and annuluses; therefore, there is no frictionalforce, which if present could erode the capsule. When moving from NEARto FAR focus it is apotheosized, the lens will move posteriorly stoppingat emmetropia even though the lens has not hit a hard stop. If thecataract surgeon leaves the patient slightly hyperopic the force isexpected to stop at the desired position of the lens to achieveemmetropia.

After cataract surgery the fibers that caused the over population of thenatural lens cavity will continue proliferation. If left unchecked theywill accumulate creating capsular opacification.

The cells are generated along the epithelium of the anterior surface ofthe natural lens (17) (see FIG. 10), which is also resting against theanterior annulus (32). As cells move distally from the prime meridian tothe anterior annulus proximal edge (31) (see FIG. 8B) many of the cellswill be scraped into the aqueous. Once the cells are surrounded byaqueous there is not a tendency for reattachment to the intraocular lensor the capsule. With movement of the optic and anterior annulus eitherposteriorly or anteriorly turbulence is created allowing additional PCOto be removed from the anterior annulus.

Once the PCO fibers are saturated with aqueous they do not have anaffinity to reattach; therefore, they are carried out of the eye throughthe trabecula meshwork and carried back to the blood stream.

Cells generated distal to the anterior annulus proximal edge willcontinue proliferation and migrate toward the posterior capsule (19)(see FIG. 10). This is true in both the NEAR and FAR positions.

In the NEAR position the anterior and posterior ribbons (34, 36) (seeFIG. 7) are part of the haptic slope (39) (see FIG. 8) allowing thecapsule to rest against it. There is little or no force between thecapsule and ribbons, so limited PCO is removed. In the FAR position theanterior capsule distal to the anterior annulus (40) and the capsularspace between the zonule attachment points (41) (see FIG. 10) is notalways in contact with the lens haptic; therefore, cells will migratetoward the posterior capsule (19) (see FIG. 12) and collect along theposterior annulus (38). Cells not scraped from the lens will arrive atthe PCO Collection Area (42) and be sandwiched between the posteriorcapsule and the annulus. With eye movement from FAR toward the NEARposition the cells will be initially squeezed from the PCO collectionarea ejecting many into the aqueous for saturation. If enough PCO iscollected around either annulus a PCO annulus can form. The squeezingfrom FAR to NEAR vision will rupture the PCO annulus, causing a portionto separate and become saturated with aqueous. The process will berepeated with each movement of the eye. In the FAR position, inside thecapsule, there is approximately one-third of the volume of aqueous asthere is in the NEAR position; therefore, aqueous (with fibrous cells)is pumped out of the capsule.

Lenses can be manufactured from hydrophobic or hydrophilic materials.One company with such materials is Contamac (Saffron Walden, UnitedKingdom). Historically, their main product for intraocular lenses hasbeen a hydrophilic material made of a copolymer of hydroxyethylmethacrylate with a 26% water content. The material squeezes into asmall cross-section allowing a small incision and opening instantly upondeparture from an injector. The surgeon can immediately position thelens. Prior to hydration the hydrophilic materials are brittle. Thewater content in hydrophobic lenses is added during the raw materialmanufacture making the material soft. The soft materials usually have tobe cooled or frozen to allow lathe turning, while the hydrophilicmaterials can be lathe turned, then hydrated. Contamac also has an 18%water content material that is stiffer and not popular because thematerial opens slowly causing the surgeon delay for centration. With a 3dimensional design as is the current invention the lens can bemanufactured using stiffer or lower water content material then squeezedinto a small profile and grasped with forceps for implantation. The lenswill open as fluid is absorbed and the materials warm to bodytemperature. As long as the lens has a round posterior surface such asis provided by an annulus and has a vertical force component the lenswill move with each change of the eye from FAR to NEAR until the lens isfully centered. With slight decentration the lens will re-center witheach accommodation cycle. See, for example, FIG. 9B. Any material withmechanical strength and optical quality that is compatible with humaneye tissue can be used.

FIG. 13 shows an alternate design replacing the cantilevered sectionwith one or more additional annuluses. The optic can be the same as thepreferred embodiment with tabs connecting to the anterior annulus andthe anterior annulus apex resting in a plane slightly higher than theapex of the lens optic. There can be additional annuluses concentric tothe anterior annulus. In any embodiment described in this specification,there can be from 1-20 annuluses, such as 1, 2, 3, 4, 5, 6, 7, 8, 9, or10 annuluses. The annulus below the anterior annulus is large enough toallow the anterior annulus outside diameter to fit inside the secondannulus. The relationship continues with the posterior annulus insidediameter larger than the outside diameter of the previous annulus. Thedesign assumes the material is more flexible and most likely having lessmechanical strength. The design is more desirable for softer materials.The number of annuluses will be determined by the strength of thematerial and the space available.

The present invention has been described with reference to particularembodiments having various features. In light of the disclosure providedabove, it will be apparent to those skilled in the art that variousmodifications and variations can be made in the practice of the presentinvention without departing from the scope or spirit of the invention.One skilled in the art will recognize that the disclosed features may beused singularly, in any combination, or omitted based on therequirements and specifications of a given application or design. Whenan embodiment refers to “comprising” certain features, it is to beunderstood that the embodiments can alternatively “consist of” or“consist essentially of” any one or more of the features. Otherembodiments of the invention will be apparent to those skilled in theart from consideration of the specification and practice of theinvention.

It is noted in particular that where a range of values is provided inthis specification, each value between the upper and lower limits ofthat range is also specifically disclosed. The upper and lower limits ofthese smaller ranges may independently be included or excluded in therange as well. The singular forms “a,” “an,” and “the” include pluralreferents unless the context clearly dictates otherwise. It is intendedthat the specification and examples be considered as exemplary in natureand that variations that do not depart from the essence of the inventionfall within the scope of the invention. Further, all of the referencescited in this disclosure are each individually incorporated by referenceherein in their entireties and as such are intended to provide anefficient way of supplementing the enabling disclosure of this inventionas well as provide background detailing the level of ordinary skill inthe art.

The invention claimed is:
 1. An intraocular lens comprising: an optic; ahaptic supporting the optic and comprising an outer annulus and an innerannulus, wherein the outer annulus has a larger radius than a radius ofthe inner annulus; wherein the inner annulus is in communication withthe outer annulus by way of a plurality of tabs and a plurality ofribbons, and a plurality of intermediate annuluses, wherein each of theribbons comprises an arcuate bend.
 2. The intraocular lens of claim 1,wherein the inner annulus is in communication with the optic by way of aplurality of tabs.
 3. The intraocular lens of claim 1, wherein the innerannulus is in communication with the outer annulus by way of at leastone intermediate annulus, and tabs connecting the inner annulus to theat least one intermediate annulus, and tabs connecting the at least oneintermediate annulus to the outer annulus.
 4. The intraocular lens ofclaim 3, wherein the at least one intermediate annulus comprises twointermediate annuluses.
 5. The intraocular lens of claim 1, wherein thearcuate bend is a 180 degree bend.
 6. The intraocular lens of claim 1,wherein the haptic is flexible and capable of disposing the optic in aposition between the inner annulus and the outer annulus.
 7. Theintraocular lens of claim 1, wherein the optic is bi-convex.
 8. Theintraocular lens of claim 1, wherein the optic is bi-aspheric.
 9. Theintraocular lens of claim 1, wherein the haptic slopes outwardly fromthe inner annulus to the outer annulus.
 10. An intraocular lenscomprising: an optic; a haptic in communication with the optic,comprising: a first annulus; a second annulus; a plurality of tabsconnecting the optic and the annuluses; wherein a cross-section of theintraocular lens along a plane perpendicular to a diameter of theintraocular lens reveals that the haptic is sloped; and wherein thefirst annulus is in communication with the second annulus by way of atleast one intermediate annulus, and tabs connecting the first annulus tothe at least one intermediate annulus, and tabs connecting the at leastone intermediate annulus to the second annulus.
 11. The intraocular lensof claim 10, wherein the haptic is flexible and capable of disposing theoptic in a position between the first annulus and the second annulus.12. The intraocular lens of claim 10, wherein the optic is bi-convex.13. The intraocular lens of claim 10, wherein the optic is bi-aspheric.14. An intraocular lens comprising: an optic; a flexible hapticcomprising an inner annulus and an outer annulus with additionalannuluses, tabs, and cantilevered structures between the inner annulusand the outer annulus configured to provide flexibility to the hapticfrom a compressed state to a relaxed state; wherein when the hapticmoves from a relaxed state to a compressed state, the inner annulusmoves posteriorly toward the outer annulus to increase the strength ofdistant vision; and wherein when the haptic moves from a compressedstate to a relaxed state, the inner annulus moves anteriorly to providefor stronger near vision.
 15. The intraocular lens of claim 14, whereinduring use by a subject the annuluses, tabs, and cantilevered structuresfunction as a spring such that the annuluses are at a maximum separationwhen the subject is viewing near objects and at a minimum separationwhen the subject is viewing far objects.
 16. The intraocular lens ofclaim 14, wherein the optic is bi-convex.
 17. The intraocular lens ofclaim 14, wherein the optic is bi-aspheric.
 18. The intraocular lens ofclaim 14, wherein the cantilevered structures comprise a plurality ofribbons.
 19. The intraocular lens of claim 18, wherein each of theribbons comprises an arcuate bend.
 20. The intraocular lens of claim 19,wherein the arcuate bend is a 180 degree bend.